In order to electrically connect a relatively small signal transfer member such as an FPC and FFC mounted on various kinds of electronic devices to an wiring board on which various electrical parts are mounted, an electrical connector electrically connected and fixed to (mounted on) the wiring board is often used.
With the electrical connector mounted on such a wiring board, when the connection part of a contact made of a conductive material and constituting the electrical connector (the part to be, for example, soldered to an electrode on the wiring board on which the electrical connector is mounted) and the housing wall surface made of an insulating material and facing the connection part are closely spaced, solder or flux may run between the connection part and housing wall surface while the wiring board and connection part are reflow-soldered. The same phenomenon occurs when the lower beam extending from the connection part and the housing wall surface facing the lower beam are closely spaced. The solder or flux may run between the lower beam and housing wall surface.
Furthermore, the solder or flux may run between the coupling part coupling the lower beam to the upper beam facing the lower beam and the housing wall surface facing the coupling part, run between the upper beam and the housing wall surface facing the upper beam, and adhere to the signal contact part provided on the upper beam (the part that can make contact with a signal terminal on the signal transfer member).
Here, the flux contains natural plant resins, such as pine resin, dissolving before the solder and removing oxides and contaminants on the fused solder surface and metal portion.
As the flux adheres to the signal contact part, the conduction between the signal contact part and the signal terminal on the signal transfer member is impaired. As an electrical connector that can prevent such a problem, for example, the connector described in Patent Literature 1 is known.
In the electrical connector described in the Patent Literature 1, the distance between the connection part and the housing wall surface facing the connection part is larger than the distance between the lower beam and the housing wall surface facing the lower beam (for example, see FIG. 11 of the Patent Literature 1). This structure prevents the solder or flux from running between the connection part and housing wall surface, in other words prevents the capillary action from occurring between the connection part and housing wall surface.
In the electrical connector described in the Patent Literature 1, the solder or flux does not run between the connection part and housing wall surface and thus the solder or flux does not run between the lower beam and housing wall surface, either. Therefore, the electrical connector described in the Patent Literature 1 can prevent the flux from adhering to the signal contact part.